Fluorescent labeling of cell surface proteins in vivo with spatiotemporal control

This technology is a fluorescent labeling technique for cell surface proteins through an in vivo adaptation of the DogTag-DogCatcher system.

Unmet Need: Direct fusion of fluorescent tags to proteins for visualization

While direct fluorescent tagging is a powerful tool for protein visualization and study, certain protein families, including some cell surface proteins, are difficult to fuse directly with a fluorescent probe. The importance of fluorescent bioimaging for in vivo research motivates the development of alternative strategies to fluorescently label difficult proteins.

The Technology: Fluorescent labeling of membrane proteins in vivo

This technology is a platform for labeling cell surface proteins in vivo that enables a wider range of target sites for labeling. To do this, this platform leverages the DogTag-DogCatcher peptide partner system, in which a spontaneous covalent isopeptide bond forms between the DogTag and DogCatcher peptides. Unlike most tags that are implemented at protein termini, DogTag can be utilized in protein loops, expanding the range of sites that can be targeted in proteins. In this platform, the DogTag is implemented into cell surface proteins through genome engineering, which enables the formation of a covalent bond with a genetically engineered DogCatcher protein fused with green fluorescent protein (GFP).

This technology has been validated in vitro on proteins located on opposing membranes to facilitate neuronal target recognition at Drosophila neuromuscular junctions.

Applications:

• Bioengineering screening and selection technique
• Versatile research tool for protein-specific tagging and functional studies analysis
• Fluorescent biopsy platform for precision medicine

Advantages:

• Enables spontaneous covalent bond formation between proteins in vivo
• Enables fluorescent tagging of a wider range of protein sites
• Rapid identification of optimal DogTag insertion sites
• Provides highly efficient protein-protein coupling
• High degree of spatiotemporal control

Lead Inventor:

Richard Mann, Ph.D.

Patent Information:

Patent Pending

Related Publications:

• Rostam KD, Morano NC, Menon KP, Lopez DH, Shapiro L, Zinn K, Feng S, Mann RS. FETCH enables fluorescent labeling of membrane proteins in vivo with spatiotemporal control in Drosophila. bioRxiv [Preprint].

Tech Ventures Reference:

• IR CU25172, CU22274

• Licensing Contact: Jerry Kokoshka